Ohm F remodel options


So, someone has offered me their Ohm F’s- all original parts with no modifications. The cabinets are rosewood, and really look like they’re about 34 years old.

The drivers are in horrible condition. The Right speaker has the surround disintegrated and is virtually un-playable. The Left is in slightly better shape, but reveals its age.

I have no idea what kind of room they will be in a year from now. The current room is too small, and in a 900-sq ft house it is a non-starter. We have no room to even store them at the moment. I would take possession of them the day that we move to Virginia, probably in April.

There seem to be quite a few options.

1) Send them to Ohm for an upgrade. But, an upgrade to what? The 2000 driver seems to be a safe bet, assuming they will be in a medium-to-small room next year. Sending them in for a full 5000 upgrade is possible, but the expense will delay the project for about a year.

2) Have Ohm send the drivers of choice and do it myself. Good option unless I go up to the 4000 or 5000 driver. I’m not that good with woodworking, and would be concerned about screwing them up.

3) Go for the gusto and send to Dale Harder and crew to be updated with their modern Walsh driver. But that expense will really delay the project.

What would you do if given Ohm F’s?
parasound63
Send them to Dale Harder or Miller sound. Forget Ohm. Better yet, send them to me!
I don't think the current Ohm drivers are the same as the "F", a true Walsh driver. As such I think you're best off with Dale Harder...

http://forum.audiogon.com/cgi-bin/fr.pl?cspkr&1015294796&read&keyw&zzohm=acoustics

http://www.hhr-exoticspeakers.com/HHRhome.htm

or Miller Sound, who I know of via a friend who's used them and was VERY pleased with the results...

http://www.millersound.net/indexfl.htm
Thanks for the responses so far. I have an email in to Dale Harder. I hadn't been aware of Miller Sound, and will definitely check it out.

-P
OHM Fs are special and deserve preservation if at all possible.

It may or may not still be possible to restore original drivers to their original glory or something close enough, I just do not know for sure. I know OHM gave up on trying to do it years ago.

Restoring the surrounds may be the easy part. I have heard that the spiders in the voice coil tend to sag from gravitational pull and such over time and that affects the sound, etc. Also the foam material used in the driver rots. Just some things to be aware of that experienced OHM F repair shops should be able to address. I would not assume just any speaker repair shop can properly repair an OHM F Walsh driver. They are much different from conventional dynamic drivers.
Hey Mapman!

Pretty sure I'll be sending them to an extremely qualified shop, if I go the restored F route.

But honestly, the Ohm X000 (new series) drivers are still in play for me, on a cost-benefit basis.

At any rate, I have at least 6 months before I can actually do anything with them. I'm just hoping for a lot of ideas and debate in the meantime so that I make the best choice.

-P
If you find a place (Miller SOund?)that can reliably restore an original F driver properly, please let us know the details of what is done to accomplish that. As I indicated, OHM Fs are a piece of sound engineering history and should be preserved if possible. IS it possible or is the sound of a properly functioning OHM F only a valued thing of the past at this point?

My understanding is that Dale Harder replaces the original driver with his own new and approved version. It may sound fantastic at that point, but it technically is an "OHM F" in general appearance only at that point. His driver is a new, different and I would assume much improved design.

My OHM F-5s use original OHM F cabinets. Though the Walsh 5 drivers have level adjustments to enable them to fit into smaller rooms, the main sound advantage of these are in larger rooms. OHM does fit smaller drivers into the larger OHM F cabinets as well. This probably provides additional bass extension versus a smaller cabinet via porting. Whether this is beneficial compared to the same CLS driver in a smaller cabinet will probably depend on the room size and layout and listener preference. Personally, I would prefer having a smaller driver and cabinet in a smaller room in that the omni Walsh drivers sound best with room around them to "breathe" IMO. For normal listening, putting my F5s in my smaller room had no practical or sound advantage over the smaller 100s that normally reside there.
Despite many claims to the contrary, these are unusual and classic drivers, very, very few have the know how to restore them. I've heard about nightmares from others who have had supposed experts completely destroy them. If the cost of restoration has you contemplating an Ohm replacement, please reconsider. Perhaps you can sell them as is, to someone willing to do it right. Original Walsh drivers are hard to find and deserve appropriate restoration. Though Dale's version might not be an exact replica of the original Walsh driver, it appears to be much closer to the original design goals than the new Ohm subsitutes.
Is there is anyone out there who has actually heard dale Harder's new Walsh speakers? Does he do any audio shows?

I would really like to know what they sound like in comparison to the newer OHM CLSs, but have not heard any accounts to-date.
Unsound- you're probably right.

Holding on to them until I find someone able and willing to restore to original condition is an option, if I can't get it done myself. I'm holding out hope that I can be that person. But first, I have to find someone that I absolutely trust to do the restoration. I'm hoping that over the next few months the fine folk here at the 'gon can help.

I have exploratory emails to both Dale Harder and Miller Sound.

Mapman- you raise I point I hadn't considered. When I move to Quantico it might be feasible for me to take a drive over to Parma and check out the Harder facility, and listen to his speakers in person. I was born in Cleveland (Lakewood) and plan on traveling to NE and NW Ohio while on the East Coast anyway.

-P
So far:

Millersound has no interest in dealing with the F's. Very polite about it though.

Speakerexpress believes that they can refurbish to original spec. Minimally invasive, and by far the most cost-effective.

Dale Harder seems genuinely enthusiastic, and wants to talk about the options. He just seems to love the F's, and his passion is incredible.

One thought I do have: I want them to remain Ohm F's, and as close to original specification as possible. Otherwise, they won't be Ohm F's...
para,

Thanks for the update.

Please keep 'em coming as things develop! I would go out of my way to be able to have a properly functioning pair of original OHM F's myself someday.
Restoring historicaly correct Walsh drivers is a noble endevor, but I wonder what Licoln Walsh would have designed if he had access to todays technology or just lessons learned. Perhaps presumptious, but perhaps using Lincoln Walsh's design as a platform for the potential that was then not plausible, but currently is, might be just as noble an effort. Of course there is a difference between evolution and devolution. Choose your path wisely grasshopper:>).
A new player has emerged to possibley work on the F's. Erik Wayne, nephew of Bill @Millersound has expressed interest in the project. He's in New Jersey, and a reasonable distance for me to drive to once I'm in Virginia.

I think I would like to avoid shipping if possible...

As far as being a noble venture, for me restoring the F is a logical course. There aren't that many in working condition.

-P
"but I wonder what Licoln Walsh would have designed if he had access to todays technology or just lessons learned"

On paper at least, the evidence would seem to suggest that Dale Harder's technical vision is closest of the variations out there to that of Lincoln Walsh's, a single full range Walsh driver, along with the pros/cons that go along with that.

German Physics and OHM are both more focused on making the design more durable and reliable IMHO.

GP is more focused on using Walsh technology from the top frequencies on down and punting on the low end so that the driver is less inclined to destroy itself and hence more robust and marketable from a support perspective. Theirs is also more a "cost is no object" marketing approach.

OHM is also more focused on all but the top frequencies, also in the interest of making the design more robust and reliable at high output levels and hence more reliable as a solution for the masses. OHMs marketing scheme is more blue colar: find ways to make the technology more affordable for the masses.

Dale Harder has apparently improved on the robustness of the Walsh driver implementation from OHMs early attempts (the F and A) but my impression is that it is still more an issue with his design than the others.
Bump-

I FINALLY hooked up the F's tonight, and they work and sound fine. Down the road I may have some work done, especially re-foaming at the very least. The dust covers are horrible looking, and the cabinets could use refinishing.

In the meantime, I have a working pair of F's in pretty good condition...
Lucky guy!

Those things are the easiest to fix, though my understanding is the refoam needs to be done by someone familair with the Fs.

IS the foam getting brittle or damaged or just not clean? There may be ways to clean and perhaps even lubricate it without replacing if not, depending.
As the original owner of a pair of Fs, The foam surrounds in mine have finally given up the ghost.   They have started to crack and separate.  The foam lining of the speaker cones remains supple and intact. 

I found this thread and wanted to ask if Parasound63 (or anyone else) has more recent info on successfully repairing  Fs, and keeping them original, and/or getting them upgraded (and feedback from doing so).
@mapman, I know this response is quite late 😄, 
but I think part of the reason GP chooses a top down approach is to keep the cross-over out of the more critical higher listening frequencies, Which might be even more noticeable with their time accurate true bending wave drivers. Also bass frequencies tend to be more sympathetic to both DSP and swarm sub-woofer approaches for the more sensitive to room variance bass frequencies.